Tingkatkan kebijakan Web Application Firewall menggunakan Azure PowerShell

Skrip ini memudahkan transisi dari konfigurasi WAF, atau kebijakan WAF khusus aturan kustom, ke kebijakan WAF penuh. Anda mungkin melihat peringatan di portal yang mengatakan tingkatkan ke kebijakan WAF, atau Anda mungkin menginginkan fitur WAF baru seperti aturan kustom Geomatch, kebijakan WAF per situs, dan kebijakan WAF per URI, atau kumpulan aturan mitigasi bot. Untuk menggunakan salah satu fitur ini, Anda memerlukan kebijakan WAF lengkap yang terkait dengan gateway aplikasi Anda.

Untuk informasi selengkapnya tentang membuat kebijakan WAF baru, lihat Membuat kebijakan Web Application Firewall untuk Application Gateway. Untuk informasi tentang migrasi, lihat memutakhirkan ke kebijakan WAF.

Untuk meng-upgrade kebijakan WAF menggunakan skrip migrasi

Gunakan langkah-langkah berikut untuk menjalankan skrip migrasi:

  1. Buka jendela Cloud Shell berikut, atau buka jendela dari dalam portal.
  2. Salin skrip ke jendela Cloud Shell dan jalankan.
  3. Skrip meminta ID Langganan, nama Grup Sumber Daya, nama Application Gateway yang terkait dengan konfigurasi WAF, dan nama kebijakan WAF baru yang Anda buat. Setelah Anda memasukkan input ini, skrip berjalan dan membuat kebijakan WAF baru Anda
  4. Verifikasi kebijakan WAF baru terkait dengan gateway aplikasi Anda. Buka kebijakan WAF di portal dan pilih tab Gateway Aplikasi Terkait . Verifikasi Application Gateway terkait dengan kebijakan WAF.

Nota

Skrip tidak menyelesaikan migrasi jika ada kondisi berikut:

  • Seluruh kumpulan aturan dinonaktifkan. Untuk menyelesaikan migrasi, pastikan seluruh grup aturan tidak dinonaktifkan.

Untuk informasi selengkapnya, lihat fungsi ValidateInput dalam skrip.

<#PSScriptInfo
.DESCRIPTION
Will be used to upgrade to the application-gateway to a top level waf policy experience.

.VERSION 1.0

.GUID b6fedd43-ebd0-41ed-9847-4f1c1c43be22

.AUTHOR Venkat.Krishnan

.PARAMETER subscriptionId 
Subscription Id of where the resources are present.
.PARAMETER resourceGroupName
Resource-group where the resources are present.
.PARAMETER applicationGatewayName
Application-Gateway name
.PARAMETER wafPolicyName
Name of the web application firewall policy

.EXAMPLE
./migrateToWafPolicy.ps1 -subscriptionId  <your-subscription-id> -applicationGatewayName <your-appgw-name> -resourceGroupName <your-resource-group-name> -wafPolicyName <new-waf-policy-name>
#>

param(
    [Parameter(Mandatory=$true)]
    [string] $subscriptionId,
    [Parameter(Mandatory=$true)]
    [string] $resourceGroupName,
    [Parameter(Mandatory=$true)]
    [string] $applicationGatewayName,
    [Parameter(Mandatory=$true)]
    [string] $wafPolicyName
)

function ValidateInput ($appgwName, $resourceGroupName) {
    # Obtain the application-gateway
    $appgw = Get-AzApplicationGateway -Name $applicationGatewayName -ResourceGroupName $resourceGroupName
    if (-not $appgw) {
        Write-Error "ApplicationGateway: $applicationGatewayName is not present in ResourceGroup: $resourceGroupName"
        return $false
    }

    # Check if already have a global firewall policy
    if ($appgw.FirewallPolicy) {
        $fp = Get-AzResource -ResourceId $appgw.FirewallPolicy.Id
        if ($fp.PolicySettings) {
            Write-Error "ApplicationGateway: $applicationGatewayName already has a global firewall policy: $fp.Name. Please use portal for changing the policy."
            return $false
        }
    }

    if ($appgw.WebApplicationFirewallConfiguration) {
        # Throw an error, since ruleGroup disabled case can't be migrated now.
        if ($appgw.WebApplicationFirewallConfiguration.DisabledRuleGroups) {
            foreach ($disabled in $appgw.WebApplicationFirewallConfiguration.DisabledRuleGroups) {
                if ($disabled.Rules.Count -eq 0) {
                    $ruleGroupName = $disabled.RuleGroupName
                    Write-Error "The ruleGroup '$ruleGroupName' is disabled. Currently we can't upgrade to a firewall policy when an entire ruleGroup is disabled. This feature will be delivered shortly. To continue, kindly ensure the entire rulegroups are not disabled. "
                    return $false
                }
            }
        }
    }

    if ($appgw.Sku.Name -ne "WAF_v2" -or $appgw.Sku.Tier -ne "WAF_v2") {
        Write-Error " Cannot associate a firewall policy to application gateway :$applicationGatewayName since the Sku is not on WAF_v2"
        return $false
    }

    return $true
}

function Login() {
    $context = Get-AzContext
    if ($null -eq $context -or $null -eq $context.Account) {
        Login-AzAccount
    }
}

function createNewTopLevelWafPolicy ($subscriptionId, $resourceGroupName, $applicationGatewayName, $wafPolicyName) {
    Select-AzSubscription -Subscription $subscriptionId
    $retVal = ValidateInput -appgwName $applicationGatewayName -resourceGroupName $resourceGroupName
    if (!$retVal) {
        return
    }

    $appgw = Get-AzApplicationGateway -Name $applicationGatewayName -ResourceGroupName $resourceGroupName

    # Get the managedRule and PolicySettings
    $managedRule = New-AzApplicationGatewayFirewallPolicyManagedRule
    $policySetting = New-AzApplicationGatewayFirewallPolicySetting
    if ($appgw.WebApplicationFirewallConfiguration) {
        $ruleGroupOverrides = [System.Collections.ArrayList]@()
        if ($appgw.WebApplicationFirewallConfiguration.DisabledRuleGroups) {
            foreach ($disabled in $appgw.WebApplicationFirewallConfiguration.DisabledRuleGroups) {
                $rules = [System.Collections.ArrayList]@()
                if ($disabled.Rules.Count -gt 0) {
                    foreach ($rule in $disabled.Rules) {
                        $ruleOverride = New-AzApplicationGatewayFirewallPolicyManagedRuleOverride -RuleId $rule
                        $_ = $rules.Add($ruleOverride)
                    }
                }
                
                $ruleGroupOverride = New-AzApplicationGatewayFirewallPolicyManagedRuleGroupOverride -RuleGroupName $disabled.RuleGroupName -Rule $rules
                $_ = $ruleGroupOverrides.Add($ruleGroupOverride)
            }
        }

        $managedRuleSet = New-AzApplicationGatewayFirewallPolicyManagedRuleSet -RuleSetType $appgw.WebApplicationFirewallConfiguration.RuleSetType -RuleSetVersion $appgw.WebApplicationFirewallConfiguration.RuleSetVersion 
        if ($ruleGroupOverrides.Count -ne 0) {
            $managedRuleSet = New-AzApplicationGatewayFirewallPolicyManagedRuleSet -RuleSetType $appgw.WebApplicationFirewallConfiguration.RuleSetType -RuleSetVersion $appgw.WebApplicationFirewallConfiguration.RuleSetVersion -RuleGroupOverride $ruleGroupOverrides
        }
    
        $exclusions = [System.Collections.ArrayList]@()  
        if ($appgw.WebApplicationFirewallConfiguration.Exclusions) {
            foreach ($excl in $appgw.WebApplicationFirewallConfiguration.Exclusions) {
                if ($excl.MatchVariable -and $excl.SelectorMatchOperator -and $excl.Selector) {
                    $exclusionEntry = New-AzApplicationGatewayFirewallPolicyExclusion -MatchVariable  $excl.MatchVariable -SelectorMatchOperator $excl.SelectorMatchOperator -Selector $excl.Selector
                    $_ = $exclusions.Add($exclusionEntry)
                }

                if ($excl.MatchVariable -and !$excl.SelectorMatchOperator -and !$excl.Selecto) {
                    # Equals Any exclusion
                    $exclusionEntry = New-AzApplicationGatewayFirewallPolicyExclusion -MatchVariable  $excl.MatchVariable -SelectorMatchOperator "EqualsAny" -Selector "*"
                    $_ = $exclusions.Add($exclusionEntry)
                }
            }
        }
    
        $managedRule = New-AzApplicationGatewayFirewallPolicyManagedRule -ManagedRuleSet $managedRuleSet
        $exclCount = $exclusions.Count
        if ($exclCount -ne 0) {
            $managedRule = New-AzApplicationGatewayFirewallPolicyManagedRule -ManagedRuleSet $managedRuleSet -Exclusion $exclusions
        }

        
        $policySetting = New-AzApplicationGatewayFirewallPolicySetting -MaxFileUploadInMb $appgw.WebApplicationFirewallConfiguration.FileUploadLimitInMb -MaxRequestBodySizeInKb $appgw.WebApplicationFirewallConfiguration.MaxRequestBodySizeInKb -Mode Detection -State Disabled
        if ($appgw.WebApplicationFirewallConfiguration.FirewallMode -eq "Prevention") {
            $policySetting.Mode = "Prevention"
        }

        if ($appgw.WebApplicationFirewallConfiguration.Enabled) {
            $policySetting.State = "Enabled"
        }

        $policySetting.RequestBodyCheck = $appgw.WebApplicationFirewallConfiguration.RequestBodyCheck;
    }

    if ($appgw.FirewallPolicy) {
        $customRulePolicyId = $appgw.FirewallPolicy.Id
        $rg = Get-AzResourceGroup -Name $resourceGroupName
        $crPolicyName = $customRulePolicyId.Substring($customRulePolicyId.LastIndexOf("/") + 1)
        $customRulePolicy = Get-AzApplicationGatewayFirewallPolicy -ResourceGroupName $rg.ResourceGroupName -Name $crPolicyName
        $wafPolicy = New-AzApplicationGatewayFirewallPolicy -ResourceGroupName $rg.ResourceGroupName -Name $wafPolicyName -CustomRule $customRulePolicy.CustomRules -ManagedRule $managedRule -PolicySetting $policySetting -Location $appgw.Location
    } else { 
        $wafPolicy = New-AzApplicationGatewayFirewallPolicy -Name $wafPolicyName -ResourceGroupName $resourceGroupName -PolicySetting $policySetting -ManagedRule $managedRule -Location $appgw.Location
    }

    if (!$wafPolicy) {
        return
    }

    $appgw.WebApplicationFirewallConfiguration = $null
    $appgw.FirewallPolicy = $wafPolicy
    $appgw = Set-AzApplicationGateway -ApplicationGateway $appgw
    Write-Host " firewallPolicy: $wafPolicyName has been created/updated successfully and applied to applicationGateway: $applicationGatewayName!"
    return $wafPolicy
}

function Main() {
    Login
    $policy = createNewTopLevelWafPolicy -subscriptionId $subscriptionId -resourceGroupName $resourceGroupName -applicationGatewayName $applicationGatewayName -wafPolicyName $wafPolicyName
    return $policy
}

Main

Langkah selanjutnya

Pelajari lebih lanjut tentang aturan dan grup aturan CRS Web Application Firewall.